LG Stove Repair in Toronto — Surface element stuck on high

• No cooktop display code is the diagnostic tell, same as the rest of this LG electric range platform: LG's F-codes are OVEN-side only (F9 = the oven failed to reach temperature within about five minutes of preheat, F11 = main board/display communication error), so a surface burner STUCK ON HIGH on an LRE/LSE/LDE smoothtop or LSEL ProBake slide-in throws no code at all. That makes a runaway burner a hardware-isolation job worked in a fixed order — knob, then the per-burner infinite switch, then any shared relay/surface-element board — not a control-board chase off a code that never appears.
• Single burner locked on full heat at every knob position = the surface element (infinite) control switch with WELDED contacts, LG EBF62174906 (OEM; verified cross-refs AP7225540 / PS17631121; same family as EBF62174901/904/907, which carries AP6037530 / PS11771631; fits LSE4613/LSE4615, LDE4413/4415, LRE4213/4813-class). The infinite switch cycles 240V to set the heat level; when its internal contacts fuse closed they feed the element continuous voltage so the zone stays on HIGH regardless of dial. Per RepairClinic the welded-contact switch is the #1 stuck-on cause — we meter the switch and look for 0-ohm/closed continuity in the OFF position, condemn that switch, and treat the burner as a live safety hazard until it's replaced.
• Before any switch comes out we rule out a cracked or stripped control KNOB, LG AEZ75853716 (OEM D-shaft knob). LG knobs seat on a D-shaped shaft; when the knob splits or the D-bore rounds out it spins on the stem without rotating the switch back to OFF, so the burner reads as 'stuck on' even though the infinite switch is fine. LG/RepairClinic guidance is to inspect the knob FIRST — a cheap knob that no longer turns the stem is a far cheaper fix than the EBF62174906 switch behind it, and a knob spinning freely on its shaft is the giveaway.
• TWO or more burners stuck on high at once shifts the suspect upstream to a WELDED RELAY on the model-coded surface-element/relay board, on the LG models that use one — the exact board part number varies by model and is confirmed against the customer's model/serial, not pinned in advance. On models built that way the board carries the cooktop relays that switch power to the zones; a relay that fuses closed feeds its element(s) continuous power so the burner stays hot with the knob OFF, and simultaneous multi-zone failure is a board signature, not two infinite switches dying at once. Note that many LG radiant smoothtops switch each burner directly through its own infinite switch with no separate relay board, so we meter to confirm the live feed comes from a board (not a stuck switch) and verify the exact board against model/serial before sourcing.
• Burner heats correctly but the HOT-SURFACE light never goes out, or the zone runs hotter than set, points at the radiant surface element itself — LG MEE64286401 or 5300W1R004A (both OEM radiant elements per RepairClinic / AppliancePartsPros / PartSelect; 5300W1R004A is the 1200W element, cross-refs AP4439131 / PS3527756). The radiant element carries an integral thermal limiter that signals the hot-surface indicator; when that limiter sticks or the coil partially shorts, the control reads the zone as permanently hot. We meter the element and its limiter at the leads before condemning the switch, since a stuck-limiter element is the most-misdiagnosed 'stuck on' behind a welded infinite switch.
• A burner that goes stuck-on right after a previous repair or a power event is a polarity/feed check, not a new part. On this 240V platform a mis-landed switch lead, a pinched harness shorting a switch wire to the live side, or a board terminal bridged during service can feed an element continuously even with good components. We re-land each switch's two probes to the correct terminals and check the harness for a shorted/bridged conductor before re-ordering an EBF62174906 switch or a surface-element/relay board, so the new part doesn't inherit the same short.
• Distinguishing a true stuck-on burner from normal cycling keeps the quote honest and the customer safe: an LG radiant zone on a high setting glows steadily and only the hot-surface light lingers as it cools — that is by design. A burner that stays glowing/HIGH with the knob in OFF, or that won't drop from full heat at lower settings, is the fault. We confirm the pattern (which zone, knob position, single vs multiple burners) before ordering, so a single welded EBF62174906 switch job isn't mis-sold as a surface-element/relay board, or vice versa — and we advise killing the range breaker until the runaway zone is repaired.

LG surface element stuck on high in Toronto — the local specifics

• The recurring LG-in-Toronto pattern for a burner stuck on high is a welded-contact infinite switch (EBF62174906) on a single zone — typically the most-used front burner — with the cracked D-shaft knob (AEZ75853716) a close second cause; when TWO zones lock on high together the call almost always lands on a welded relay in the model-coded surface-element/relay board (the exact board confirmed by model/serial) rather than two switches failing at once.
• We roll to these Toronto stuck-on calls carrying the EBF62174906 infinite switch (and the EBF62174901/904/907 family variants), the AEZ75853716 D-shaft knob, and a radiant element (MEE64286401 / 5300W1R004A) for the stuck-limiter case — the model-coded surface-element/relay board we confirm by model/serial and source for the multi-burner jobs, and we advise the customer to kill the range breaker until the runaway zone is fixed.

For the full LG stove module — every fault, part number and code — see LG stove repair in Toronto, and for the same fault across all brands the stove surface element stuck on high guide.